mothers day gifts Feature:1. Boil the liquid with your and observe how the liquid boils and rises through the tubes into the upper container.2. It is a looped and twisted glass containing a liquid that will ''boil'' as heat is transferred from your bare hand, very interesting.3. Once leave your hand, it takes a few minutes for the liquid to cool down and return to the large bulb. This is a very interesting science toy and a great demonstration of energy transfer.4. This toy proves the vapour-liquid equilibrium, the colored liquid in the toy is a volatile mixture with a boiling point just above room temperature.5. The heat on your hands causes the liquid to boil, and the boiling evaporates the liquid into a gas. The expanding gas pushes the liquid upward, and when you release your hand, the equilibrium is re-established. The gas condenses again into a liquid and flows back down the lower bulb.Spec:Condition: 100% Brand NewItem Type: ToyMaterial: High Borosilicate GlassProduct Size: Approx. 16.5 x 5 cm / 6.5 x 2 inWeight: Approx. 67g / 2.4oz Package List:1 x ToyNotice:1. Please allow 0-2 cm error due to manual measurement. Thanks for your understanding.2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard.